[Dovecot] problem with default_mail_env

I'v set the default_mail_env to maildir:/var/maildir/%d/%u where /var/maildir/ is the root dorectory for my maildir tree and I'm getting the folowing error in the maillog : Jan 3 15:16:58 websrv pop3(roi): unlink(/var/maildir//roi/cur/new:2,T) failed: Is a directory Notice that the %d is missing. If I change to 'default_mail_env = maildir:/var/maildir/example.tld/%u' then it's all working fine only I can't create other virtual domains.

If anybody can help me solve this one...